Eukaryotic Translation Initiation Factor 1A, X-Chromosomal (EIF1AX) is an essential eukaryotic translation initiation factor that belongs to the eIF-1A family. EIF1AX is required for the binding of the 43S complex (a 40S subunit, eIF2/GTP/Met-tRNAi and eIF3) to the 5' end of capped RNA and has been shown to interact with IPO13. EIF1AX contains one S1-like domain and seems to be required for maximal rate of protein biosynthesis. Enhances ribosome dissociation into subunits and stabilizes the binding of the initiator Met-tRNA(I) to 40 S ribosomal subunits.